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    <title>Document</title>
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<script>

    // console.log( [].__proto__ === Array.prototype );
    // console.log( {}.__proto__ === Array.prototype );
    // console.log( new Date().__proto__ === Date.prototype );
    // console.log( new RegExp().__proto__ === RegExp.prototype );

    // console.log( undefined instanceof Object );
    // console.log( null instanceof Object );
    // console.log( [] instanceof Array );
    // console.log( {} instanceof Array );
    // console.log( new Date() instanceof Array );

    // console.log(Object.prototype.isPrototypeOf( null ))
    // console.log(Object.prototype.isPrototypeOf( undefined ))
    // console.log(Array.prototype.isPrototypeOf( [] ))
    // console.log(Array.prototype.isPrototypeOf( {} ))
    // console.log(Date.prototype.isPrototypeOf( [] ))

    // undefined.toString()
    // null.toString()
    // 123.toString()

    // console.log( Object.prototype.toString.call(undefined) )
    // console.log( Object.prototype.toString.call(null) )
    // console.log( Object.prototype.toString.call(123) )
    // console.log( Object.prototype.toString.call(NaN) )
    // console.log( Object.prototype.toString.call(true) )
    // console.log( Object.prototype.toString.call(new RegExp("a")) )
    // console.log( Object.prototype.toString.call(new Date()) )






    
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